Bank Innovation tracks financial iPhone apps, and if you’ve been following our related posts, you will have seen that the 20 most-downloaded apps have remained steady. This week, however, Capital One Financial Corp. reached the top spot among most downloaded apps for the first time on the back of its important 3.0 update, which took place yesterday.

We’ve also been tracking the features and customer satisfaction with the big banks’ smartphone apps, and while iPhone customers can be very particular about their apps, this Capital One update seems to have charmed them. The three most recent reviews at the time of this writing were highly positive: four or five stars. For example: “Awesome – [T]he new version rocks!”

What’s “awesome” about it? The app is redesigned from top to toes and optimized for the iPhone 5 ‘s taller screen. The navigation has been enlarged and moved from a small dark bar at the bottom of the screen to a larger bright blue bar up top. See the new interface at right.

Additionally, customers can interact with Capital One via Twitter and Facebook directly from within the app. This is a smart way to tie in customers’ social media use with mobile banking use. The rewards associated with credit cards are also fully accessible from the app, but one commentator notes that this is not true for checking account rewards.

The other shortfall noted by those who submitted comments is the lack of an iPad-specific app. (Capital One’s general app works on the iPad, but it is not specially designed for iPad use.) We hope Capital One is at work on this, because as we’ve seen at Finovate and BAI Retail Delivery, for example, that tablet banking is on the rise and beautiful tablet-specific solutions are out there. As Mickey Goldwasser of online banking platform creator Q2Ebanking told Bank Innovation recently, “We believe the tablet will be the optimal medium for banking going forward.”